<template>
  <div class="upload-file">
    <el-upload
      :multiple="multiple"
      :action="uploadFileUrl"
      :before-upload="handleBeforeUpload"
      :file-list="fileList"
      :limit="limit"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      :on-success="handleUploadSuccess"
      :show-file-list="false"
      :headers="headers"
      class="upload-file-uploader"
      ref="fileUpload"
    >
      <!-- 上传按钮 -->
      <el-button icon="Plus" type="primary" style="width: 261px; height: 35px; max-width: 13vw">上传标准文件</el-button>
    </el-upload>
    <!-- 上传提示 -->
    <div class="el-upload__tip" v-if="showTip">
      请上传
      <template v-if="fileSize">
        大小不超过
        <b style="color: #f56c6c">{{ fileSize }}MB</b>
      </template>
      <template v-if="fileType">
        格式为
        <b style="color: #f56c6c">{{ fileType.join('/') }}</b>
      </template>
      的文件
    </div>
    <!-- 文件列表 -->
    <transition-group
      v-if="isShowList"
      class="upload-file-list el-upload-list el-upload-list--text"
      name="el-fade-in-linear"
      tag="ul"
    >
      <li :key="file.uid" class="el-upload-list__item ele-upload-list__item-content" v-for="(file, index) in fileList">
        <el-link :href="`${baseUrl}${file.url}`" :underline="false" target="_blank">
          <span class="el-icon-document">{{ getFileName(file.name) }}</span>
        </el-link>
        <div class="ele-upload-list__item-content-action">
          <el-link :underline="false" @click="handleDelete(index)" type="danger">删除</el-link>
        </div>
      </li>
    </transition-group>
  </div>
</template>

<script setup>
  import { getToken } from '@/utils/auth';

  const { proxy } = getCurrentInstance();

  const props = defineProps({
    modelValue: [String, Object, Array],
    // 请求路径
    uploadUrl: {
      type: String,
      default: '/resource/oss/upload',
    },
    // 数量限制
    limit: {
      type: Number,
      default: 9,
    },
    // 是否支持多选文件
    multiple: {
      type: Boolean,
      default: false,
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 500,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ['pdf'],
    },
    // 是否显示文件列表
    isShowList: {
      type: Boolean,
      default: false,
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: false,
    },
  });

  const emit = defineEmits();
  const number = ref(0);
  const uploadList = ref([]);
  const baseUrl = import.meta.env.VITE_APP_BASE_API;
  const uploadFileUrl = process.env.VITE_APP_BASE_API + props.uploadUrl;
  const headers = ref({ Authorization: 'Bearer ' + getToken() });
  const fileList = ref([]);
  const showTip = computed(() => props.isShowTip && (props.fileType || props.fileSize));

  watch(
    () => props.modelValue,
    val => {
      if (val) {
        let temp = 1;
        // 首先将值转为数组
        const list = Array.isArray(val) ? val : props.modelValue.split(',');

        // 然后将数组转为对象数组
        fileList.value = list.map(item => {
          if (typeof item === 'string') {
            item = { id: item.id, name: item.name, url: item.url };
          }
          item.uid = item.uid || new Date().getTime() + temp++;
          return item;
        });
      } else {
        fileList.value = [];
        return [];
      }
    },
    { deep: true, immediate: true }
  );

  // 上传前校检格式和大小
  function handleBeforeUpload(file) {
    // 校检文件类型
    if (props.fileType.length) {
      const fileName = file.name.split('.');
      const fileExt = fileName[fileName.length - 1];
      const isTypeOk = props.fileType.indexOf(fileExt) >= 0;
      if (!isTypeOk) {
        proxy.$modal.msgError(`文件格式不正确, 请上传${props.fileType.join('/')}格式文件!`);
        return false;
      }
    }
    // 校检文件大小
    if (props.fileSize) {
      const isLt = file.size / 1024 / 1024 < props.fileSize;
      if (!isLt) {
        proxy.$modal.msgError(`上传文件大小不能超过 ${props.fileSize} MB!`);
        return false;
      }
    }
    proxy.$modal.loading('正在上传文件，请稍候...');
    number.value++;
    return true;
  }

  // 文件个数超出
  function handleExceed() {
    proxy.$modal.msgError(`最多上传${props.limit}个文件`);
  }

  // 上传失败
  function handleUploadError(err) {
    proxy.$modal.msgError('上传文件失败');
    proxy.$modal.closeLoading();
  }

  // 上传成功回调
  function handleUploadSuccess(res, file) {
    if (res.code === 200) {
      uploadList.value.push({ id: res.data.id, url: res.data.url, name: res.data.name });
      uploadedSuccessfully();
    } else {
      number.value--;
      proxy.$modal.closeLoading();
      proxy.$modal.msgError(res.message);
      proxy.$refs.fileUpload.handleRemove(file);
      uploadedSuccessfully();
    }
  }

  // 删除文件
  function handleDelete(index) {
    fileList.value.splice(index, 1);
    emit('update:modelValue', fileList.value);
  }

  // 上传结束处理
  function uploadedSuccessfully() {
    if (number.value > 0 && uploadList.value.length === number.value) {
      fileList.value = fileList.value.filter(f => f.url !== undefined).concat(uploadList.value);
      uploadList.value = [];
      number.value = 0;
      emit('update:modelValue', fileList.value);
      emit('successfully');
      proxy.$modal.closeLoading();
    }
  }

  // 获取文件名称
  function getFileName(name) {
    if (name.lastIndexOf('/') > -1) {
      return name.slice(name.lastIndexOf('/') + 1);
    } else {
      return '';
    }
  }

  // 对象转成指定字符串分隔
  function listToString(list, separator) {
    let strs = '';
    separator = separator || ',';
    for (let i in list) {
      if (list[i].url) {
        strs += list[i].url + separator;
      }
    }
    return strs != '' ? strs.substr(0, strs.length - 1) : '';
  }
</script>

<style scoped lang="scss">
  .upload-file-uploader {
    margin-bottom: 5px;
  }
  .upload-file-list .el-upload-list__item {
    border: 1px solid #e4e7ed;
    line-height: 2;
    margin-bottom: 10px;
    position: relative;
  }
  .upload-file-list .ele-upload-list__item-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: inherit;
  }
  .ele-upload-list__item-content-action .el-link {
    margin-right: 10px;
  }
  .el-button:focus {
    color: var(--el-button-text-color) !important;
    border-color: var(--el-button-border-color) !important;
    background-color: var(--el-button-bg-color) !important;
    outline: 0;
  }

  .el-button:hover {
    color: var(--el-button-text-color) !important;
    border-color: var(--el-button-border-color) !important;
    background-color: var(--el-button-bg-color) !important;
    outline: 0;
  }

  .el-button:active {
    color: var(--el-button-text-color) !important;
    border-color: var(--el-button-border-color) !important;
    background-color: var(--el-button-bg-color) !important;
    outline: 0;
  }
</style>
